An intrauterine device, also known as an IUD, is a birth control device placed in the uterus as a method of reversible birth control. IUDs have been known and patented since the 19th century. IUDs currently are T-shaped, and sized to fit entirely within the average adult female. Previous designs included IUDs having a shape of the number 7 or the capital greek letter omega, among others.
IUDs prevent pregnancy either through the slow release of a pregnancy-preventing substance such as copper or the hormone levonorgestrel into the uterus.
As exemplified in FIG. 1, IUDs currently on the market are manufactured with one or more strings extending from the bottom of the IUD. These strings are provided to serve the purposes of IUD adjustment and removal. When the body of the IUD is placed in the uterus, the string(s) extend through the cervix and, ideally at least, remain positioned in the vaginal cavity.
The strings are manufactured of any materials known to be safe when placed in the body over an extended period of time such as a monofilament polyethylene string or a metal-coated string.
It is believed that the metal layer prevents bacteria and other infection-causing agents from entering the cervix and traveling to the uterus, or at least reduces the distance that these agents travel into the cervix.
After placing the IUD in the uterus, physicians cut the strings to a length that they believe is comfortable for the woman. The exact preferred length, however, is merely a guess. If a string is left too long, it can become displaced to the point that it may hang out of the woman's vagina, become entangled with tampons, or cause discomfort for the woman's sex partner.
It is also common for physicians to wrap the string(s) around the cervix in an effort to minimize distraction for women and their sex partners, but this practice is largely dependent on physician training or preference, and, in any case, there is no guarantee that the string will remain in the wrapped position.
Further, if the string is cut too short, or at an angle at the tip, it can cause serious discomfort or even pain for both the users and their partners.
In all cases, there is a known risk that the position of the IUD changes after insertion. The IUD may slide too far in the uterus, thus decreasing the effectiveness of the IUD. This also increases the difficulty of extraction because the string(s) cannot be located by the user or the physician.
In all cases, it is also known that the IUD may be expelled without the user noticing, thus putting her at risk of pregnancy without knowing she is at risk.
It is also known that when a user wears tampons, she can accidentally pull the IUD out or out of the ideal position when extracting the tampon because the strings of traditional IUD's become entangled or otherwise semi-attached to the tampon.
It is also known that a woman's uterus does not remain in a fixed location within her body. Particularly in women with weak cardinal ligaments and other supporting structures (e.g., uterosacral ligaments), the location of the entire uterus in relation to that of the vagina changes, not just over a long period of time, but sometimes over the course of a single day. Because the distance that the uterus drops can be significant, even as much as 5 cm, an IUD string cut to fit perfectly in the morning hours—when a woman's structure is strong—may actually hang out of the vagina by the afternoon, after the uterus has dropped in the course of the day.
No traditional IUD cures all of these deficiencies and provides a person a simple way of holding an IUD in place without interfering with sex and also provides a simple way of extracting the IUD.